Outdated Dependency -- nom

## context

I am currently working on a CLI that will take `.fountain` files and export formatted `.pdf` files; I am using your Fountain parser to achieve this.

## problem

Currently, I cannot get the library working. I cannot figure out how to call it properly. I know it returns a Result with a tuple containing the `&str` (unparsed contents, I believe) and a `Document` (parsed contents). I cannot figure out what Error type it accepts. It's using strange Error types that are hard to account for and use (ex. `VerboseError<&str>`, `IResult<&'a str, Document, E>`).

In my attempts to get it working, I saw that the `nom` you are using in `v0.1.12` is outdated. I don't know if this is contributing to my issues at all, but I felt it was worth at least posting an issue about it.

Let me know how I can help fix this problem!